Geometry and Physics Seminar: Daniel Robbins

From a target space perspective, T-duality relates certain pairs of string theory backgrounds with a U(1) isometry. If we perform a Kaluza-Klein reduction on the corresponding circle, T-duality then acts as a symmetry of the reduced theory, and this symmetry can be argued to constrain the higher derivative couplings, which in turn constrains the couplings of the higher dimensional theory. I will explain an unsophisticated brute force implementation of this procedure and show how it can be used to completely fix the four-derivative action of type II O-planes coupling to NS-NS sector bulk fields.